U.S. patent application number 16/080625 was filed with the patent office on 2019-03-07 for compressed air energy storage power generation apparatus.
This patent application is currently assigned to Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.). The applicant listed for this patent is Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.). Invention is credited to Yohei KUBO, Masaki MATSUKUMA, Kanami SAKAMOTO, Hiroki SARUTA, Masatake TOSHIMA.
Application Number | 20190072032 16/080625 |
Document ID | / |
Family ID | 59851656 |
Filed Date | 2019-03-07 |
![](/patent/app/20190072032/US20190072032A1-20190307-D00000.png)
![](/patent/app/20190072032/US20190072032A1-20190307-D00001.png)
![](/patent/app/20190072032/US20190072032A1-20190307-D00002.png)
![](/patent/app/20190072032/US20190072032A1-20190307-D00003.png)
![](/patent/app/20190072032/US20190072032A1-20190307-D00004.png)
![](/patent/app/20190072032/US20190072032A1-20190307-D00005.png)
![](/patent/app/20190072032/US20190072032A1-20190307-D00006.png)
![](/patent/app/20190072032/US20190072032A1-20190307-D00007.png)
![](/patent/app/20190072032/US20190072032A1-20190307-D00008.png)
![](/patent/app/20190072032/US20190072032A1-20190307-D00009.png)
![](/patent/app/20190072032/US20190072032A1-20190307-D00010.png)
View All Diagrams
United States Patent
Application |
20190072032 |
Kind Code |
A1 |
KUBO; Yohei ; et
al. |
March 7, 2019 |
COMPRESSED AIR ENERGY STORAGE POWER GENERATION APPARATUS
Abstract
A compressed air energy storage (CAES) power generation
apparatus includes a motor driven by renewable energy, a compressor
driven by the motor, a pressure accumulating tank storing
compressed air compressed by the compressor, an expander driven by
the compressed air from the pressure accumulating tank, and a
generator connected to the expander. The apparatus includes a first
heat exchanger that performs heat exchange between the compressed
air from the compressor to the pressure accumulating tank and a
heat medium, cools the compressed air, and heats the heat medium, a
heat accumulating tank that stores the heat medium heated by the
first heat exchanger, a second heat exchanger that performs heat
exchange between the compressed air from the pressure accumulating
tank to the expander, heats the compressed air, and cools the heat
medium, and third heat exchangers that perform heat exchange
between the exhaust heat outside a system and a fluid in the
system. The power generation efficiency of the apparatus is
improved using the exhaust heat outside the system while the
exhaust heat outside the system is cooled using the cold heat
generated in the system of the apparatus.
Inventors: |
KUBO; Yohei; (Kobe-shi,
Hyogo, JP) ; TOSHIMA; Masatake; (Kobe-shi, Hyogo,
JP) ; SARUTA; Hiroki; (Takasago-shi, Hyogo, JP)
; MATSUKUMA; Masaki; (Takasago-shi, Hyogo, JP) ;
SAKAMOTO; Kanami; (Takasago-shi, Hyogo, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.) |
Hyogo |
|
JP |
|
|
Assignee: |
Kabushiki Kaisha Kobe Seiko Sho
(Kobe Steel, Ltd.)
Hyogo
JP
|
Family ID: |
59851656 |
Appl. No.: |
16/080625 |
Filed: |
February 10, 2017 |
PCT Filed: |
February 10, 2017 |
PCT NO: |
PCT/JP2017/004904 |
371 Date: |
August 28, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
Y02E 10/72 20130101;
F05D 2220/60 20130101; F02C 7/143 20130101; Y02E 70/30 20130101;
F02C 7/10 20130101; F05D 2260/42 20130101; F03D 9/17 20160501; F05D
2260/211 20130101; F02C 7/08 20130101; Y02E 50/10 20130101; F02C
1/04 20130101; F05D 2260/213 20130101; F02C 6/16 20130101; F02C
6/18 20130101; Y02E 60/16 20130101 |
International
Class: |
F02C 6/16 20060101
F02C006/16; F02C 7/10 20060101 F02C007/10; F02C 7/143 20060101
F02C007/143; F03D 9/17 20060101 F03D009/17; F02C 1/04 20060101
F02C001/04 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 18, 2016 |
JP |
2016-055641 |
Claims
1. A compressed air energy storage power generation apparatus
comprising: an electric motor driven by power generated by
renewable energy; a compressor driven by the electric motor to
compress air; a pressure accumulator that stores the compressed air
compressed by the compressor; an expander driven by the compressed
air supplied from the accumulator; a generator mechanically
connected to the expander; a first heat exchanger that performs
heat exchange between the compressed air supplied from the
compressor to the pressure accumulator and a heat medium, cools the
compressed air, and heats the heat medium; a heat accumulator that
stores the heat medium heated by the first heat exchanger; a second
heat exchanger that performs heat exchange between the compressed
air supplied from the pressure accumulator to the expander and the
heat medium supplied from the heat accumulator, heats the
compressed air, and cools the heat medium; and a third heat
exchanger that performs heat exchange between exhaust heat outside
a system and a fluid in the system.
2. The compressed air energy storage power generation apparatus
according to claim 1, wherein the third heat exchanger performs
heat exchange between the exhaust heat outside the system and the
heat medium supplied from the first heat exchanger to the heat
accumulator, cools the exhaust heat, and heats the heat medium.
3. The compressed air energy storage power generation apparatus
according to claim 1, wherein the third heat exchanger performs
heat exchange between the exhaust heat outside the system and the
heat medium supplied from the heat accumulator to the second heat
exchanger, cools the exhaust heat, and heats the heat medium.
4. The compressed air energy storage power generation apparatus
according to claim 1, wherein the third heat exchanger performs
heat exchange between the exhaust heat outside the system and the
heat medium supplied to the heat accumulator without passing
through the first heat exchanger, cools the exhaust heat outside
the system, and heats the heat medium.
5. The compressed air energy storage power generation apparatus
according to claim 1, wherein the third heat exchanger performs
heat exchange between the exhaust heat outside the system and the
compressed air supplied from the pressure accumulator to the
expander, cools the exhaust heat outside the system, and heat the
compressed air.
6. The compressed air energy storage power generation apparatus
according to claim 1, wherein the third heat exchanger performs
heat exchange between the exhaust heat outside the system and the
air discharged from the expander, cools the exhaust heat outside
the system, and heats the air.
7. The compressed air energy storage power generation apparatus
according to claim 1, wherein the third heat exchanger performs
heat exchange between the exhaust heat outside the system and the
heat medium supplied from the second heat exchanger, cools the
exhaust heat outside the system, and heats the heat medium.
Description
TECHNICAL FIELD
[0001] The present invention relates to a compressed air energy
storage power generation apparatus.
BACKGROUND ART
[0002] In power generation, such as wind power generation and solar
power generation, in which renewable energy is used, power output
may fluctuate to become unstable because the power generation
depends on a weather conditions. A compressed air energy storage
(CAES) system is known as a system that levels the output for the
output fluctuation.
[0003] In a compressed air energy storage (CAES) power generation
apparatus in which the CAES system is used, electric energy is
stored as compressed air during a off-peak time of a power plant,
an expander is driven by the compressed air during a high-power
demand time to operate a generator, and the electrical energy is
generated to level the output. A system, in which compression heat
is recovered in a heat accumulating medium and stored in a heat
accumulating tank or the like, and the compressed air before
expansion is heated using the recovered compression heat, is known
in order to improve power generation efficiency. Consequently, a
power increase is prevented during compression, and heat
dissipation is prevented during storage of the compressed air in a
pressure accumulating tank at the same time as recovery power is
increased during the expansion.
[0004] As the CAES power generation apparatus, for example, Patent
Document 1 discloses a CAES power generation apparatus in which a
heat energy storage system is used.
[0005] Although it is different from the CAES power generation
apparatus, for example, Patent Document 2 discloses an exhaust heat
recovery apparatus that can obtain hot water or the like by
effectively using exhaust heat outside the system such as exhaust
heat of an engine.
PRIOR ART DOCUMENT
Patent Document
[0006] Patent Document 1: JP 2013-509530 A [0007] Patent Document
2: JP 5563176 B
SUMMARY OF THE INVENTION
Problems to be Solved by the Invention
[0008] In Patent Document 1, the improvement of the power
generation efficiency of the CAES power generation apparatus using
the exhaust heat outside the system is not considered. In Patent
Document 2, the reduction of the exhaust heat outside the system
using the cold heat generated in the system is not considered.
[0009] An object of the present invention is to improve the power
generation efficiency of the CAES power generation apparatus using
the exhaust heat outside the system while cooling the exhaust heat
outside the system using the cold heat generated in the system of
the CAES power generation apparatus.
Means for Solving the Problems
[0010] According to one aspect of the present invention, a
compressed air energy storage power generation apparatus includes:
an electric motor driven by power generated by renewable energy; a
compressor driven by the electric motor to compress air; a pressure
accumulator that stores the compressed air compressed by the
compressor: an expander driven by the compressed air supplied from
the accumulator; a generator mechanically connected to the
expander; a first heat exchanger that performs heat exchange
between the compressed air supplied from the compressor to the
pressure accumulator and a heat medium, cools the compressed air,
and heats the heat medium; a heat accumulator that stores the heat
medium heated by the first heat exchanger; a second heat exchanger
that performs heat exchange between the compressed air supplied
from the pressure accumulator to the expander and the heat medium,
heats the compressed air, and cools the heat medium; and a third
heat exchanger that performs heat exchange between exhaust heat
outside a system and a fluid in the system.
[0011] According to this configuration, the exhaust heat outside
the system can be cooled using the cold heat generated in the
system of the CAES power generation apparatus. Additionally, the
power generation efficiency of the CAES power generation apparatus
can be improved by heating the compressed air in an expansion stage
using the exhaust heat outside the system. Specifically, the
exhaust heat outside the system is cooled by using the cold heat
generated in the system of the CAES power generation apparatus in
the third heat exchanger, so that energy efficiency is improved as
a whole by effectively using the cold energy in the system. In
particular, in the cooling of the exhaust heat, a temperature of
the exhaust heat preferably lowered less than or equal to an
exhaust heat reference temperature using a temperature sensor or
the like. The exhaust heat reference temperature is determined by a
law, and is an upper limit value of the temperature of the exhaust
heat that can be discharged to the outside air. The compressed air
supplied to the expander by the exhaust heat outside the system is
directly or indirectly heated by the third heat exchanger, so that
the power generation efficiency of the generator is improved. The
compression heat is recovered from the compressed air to the heat
medium by the first heat exchanger, so that the temperature of the
compressed air supplied to the pressure accumulator is lowered to
prevent a heat energy loss due to the heat radiation in the
pressure accumulator. The heat medium in which the temperature is
raised by recovering the compression heat is stored in the heat
accumulator, and the compressed air before expansion is heated by
the second heat exchanger by using the heat medium in which the
temperature is raised so that operation efficiency is improved in
the expander to improve the power generation efficiency.
[0012] Preferably, the third heat exchanger performs heat exchange
between the exhaust heat outside the system and the heat medium
supplied from the first heat exchanger to the heat accumulator,
cools the exhaust heat, and heats the heat medium.
[0013] According to this configuration, in the third heat
exchanger, the heat medium heated by the first heat exchanger can
be further heated, and the higher-temperature heat medium can be
stored in the heat accumulator. This configuration is effective in
the case that the exhaust heat outside the system is higher than
the heat medium heated by the first heat exchanger.
[0014] Preferably, the third heat exchanger performs heat exchange
between the exhaust heat outside the system and the heat medium
supplied from the heat accumulator to the second heat exchanger,
cools the exhaust heat, and heats the heat medium.
[0015] According to this configuration, in the third heat
exchanger, the heat medium heated by the second heat exchanger can
be preheated, and a heating load of the heat medium in the second
heat exchanger can be reduced. This configuration is effective in
the case that the exhaust heat outside the system is higher than
the heat medium supplied to the second heat exchanger.
[0016] Preferably, the third heat exchanger performs heat exchange
between the exhaust heat outside the system and the heat medium
supplied to the heat accumulator without passing through the first
heat exchanger, cools the exhaust heat outside the system, and
heats the heat medium.
[0017] According to this configuration, in the third heat
exchanger, the heat medium supplied to the heat accumulator can be
heated in parallel with the heating of the heat medium in the first
heat exchanger, and to the more heat medium can be accumulated in
the heat accumulator. This configuration is effective in the case
that the exhaust heat outside the system is higher than the heat
medium supplied to the first heat exchanger.
[0018] Preferably, the third heat exchanger performs heat exchange
between the exhaust heat outside the system and the compressed air
supplied from the pressure accumulator to the expander, cools the
exhaust heat outside the system, and heat the compressed air.
[0019] According to this configuration, in the third heat
exchanger, the compressed air before expansion can directly be
heated using the exhaust heat with no use of the heat medium or the
like. This configuration is effective in the case that the exhaust
heat outside the system is higher than the compressed air supplied
to the expander.
[0020] Preferably, the third heat exchanger performs heat exchange
between the exhaust heat outside the system and the air discharged
from the expander, cools the exhaust heat outside the system, and
heats the air.
[0021] According to this configuration, in the third heat
exchanger, the exhaust heat outside the system can be cooled using
the cold heat of the air discharged from the expander. The
temperature of the air exhausted from the expander is lowered by
heat absorption during the expansion, and the energy efficiency of
the system can be improved by effectively using the cold heat of
the exhausted air.
[0022] Preferably, the third heat exchanger performs heat exchange
between the exhaust heat outside the system and the heat medium
supplied from the second heat exchanger, cools the exhaust heat
outside the system, and heats the heat medium.
[0023] According to this configuration, in the third heat
exchanger, the exhaust heat outside the system can be cooled using
the heat medium cooled by the second heat exchanger. Additionally,
the energy efficiency of the system can be improved by effectively
using the heat medium cooled by the second heat exchanger.
Effect of the Invention
[0024] According to the present invention, the power generation
efficiency of the CAES power generation apparatus can be improved
using the exhaust heat outside the system while the exhaust heat
outside the system is cooled using the cold heat generated in the
system of the CAES power generation apparatus.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] FIG. 1 is a schematic configuration diagram illustrating a
compressed air energy storage power generation apparatus according
to a first embodiment of the present invention; FIG. 2 is a
schematic configuration diagram illustrating a compressed air
energy storage power generation apparatus according to a second
embodiment of the present invention; FIG. 3 is a schematic
configuration diagram illustrating a compressed air energy storage
power generation apparatus according to a third embodiment of the
present invention; FIG. 4 is a schematic configuration diagram
illustrating a compressed air energy storage power generation
apparatus according to a fourth embodiment of the present
invention; FIG. 5 is a schematic configuration diagram illustrating
a compressed air energy storage power generation apparatus
according to a fifth embodiment of the present invention; FIG. 6 is
a schematic configuration diagram illustrating a compressed air
energy storage power generation apparatus according to a sixth
embodiment of the present invention; FIG. 7 is a schematic
configuration diagram illustrating a compressed air energy storage
power generation apparatus according to a seventh embodiment of the
present invention; FIG. 8A is a flowchart illustrating a method for
controlling the compressed air energy storage power generation
apparatus in FIG. 7; FIG. 8B is a flowchart illustrating a method
for controlling the compressed air energy storage power generation
apparatus in FIG. 7; FIG. 9A is a schematic configuration diagram
illustrating a compressed air energy storage power generation
apparatus according to an eighth embodiment of the present
invention; FIG. 9B is a schematic configuration diagram
illustrating the compressed air energy storage power generation
apparatus of the eighth embodiment of the present invention.
DESCRIPTION OF EMBODIMENTS
[0026] Hereinafter, embodiments of the present invention will be
described with reference to the accompanying drawings.
First Embodiment
[0027] A compressed air energy storage (CAES) power generation
apparatus 2 levels output fluctuation of a power generation device
4, which generates power by using renewable energy, to supply the
power to a power system 6, and supplies the power according to
fluctuation of power demand in the power system 6.
[0028] A configuration of the CAES power generation apparatus 2
will be described with reference to FIG. 1. The CAES power
generation apparatus 2 of the first embodiment includes air
passages 8a to 8d (illustrated by a broken line), heat medium
passages 10a to 10c (illustrated by a solid line), and exhaust heat
passages 12a to 12d (indicated by a one-dot chain line).
[0029] (Air Passage)
[0030] A compressor 16 driven by a motor (electric motor) 14, a
first heat exchanger 18, a pressure accumulating tank (pressure
accumulator) 20, a second heat exchanger 22, and an expander 26
that drives a generator 24 are sequentially provided in the air
passages 8a to 8d.
[0031] The power generation device 4 in which the renewable energy
is used is electrically connected to the motor 14 (indicated by a
two-dot chain line). The power generated by the power generation
device 4 is supplied to the motor 14. The motor 14 is mechanically
connected to the compressor 16, and the compressor 16 is driven in
association with drive of the motor 14.
[0032] When being driven by the motor 14, the compressor 16 sucks
air from an inlet port 16a through the air passage 8a, compresses
the air in the compressor 16, and discharges the compressed air
from a discharge port 16b. The discharge port 16b of the compressor
16 is fluidly connected to the pressure accumulating tank 20
through the air passage 8b, and the compressed air discharged from
the discharge port 16b is pressure-fed to the pressure accumulating
tank 20 through the air passage 8b. A type of the compressor 16 is
not particularly limited. For example, a screw type, a scroll type,
a turbo type, and a reciprocating type may be used.
[0033] The compressed air discharged from the discharge port 16b of
the compressor 16 becomes a high temperature due to the compression
heat generated during the compression, so that the compressed air
is preferably cooled before supplied to the pressure accumulating
tank 20. Thus, the first heat exchanger 18 is interposed in the air
passage 8b. In the first heat exchanger 18, by heat exchange
between a heat medium and the compressed air, the compressed air is
cooled and the heat medium is heated. Because the compression heat
is recovered from the compressed air to the heat medium by the
first heat exchanger 18 in this manner, the temperature of the
compressed air supplied to the pressure accumulating tank 20 falls,
and the compressed air is prevented from radiating heat to lose
heat energy while the compressed air is stored in the pressure
accumulating tank 20.
[0034] The pressure accumulating tank 20 can store the compressed
air, and accumulate the compressed air as energy. The pressure
accumulating tank 20 is fluidly connected to an air supply port 26a
of the expander 26 through the air passage 8c, and the compressed
air sent out from the pressure accumulating tank 20 is supplied to
the expander 26 through the air passage 8c.
[0035] In the expander 26, a temperature of the air falls due to
heat absorption during expansion. Consequently, the compressed air
supplied to the expander 26 is preferably high temperature. Thus,
the second heat exchanger 22 is interposed in the air passage 8c.
In the second heat exchanger 22, the compressed air is heated by
the heat exchange between the heat medium and the compressed air,
and the heat medium is cooled.
[0036] The expander 26 is mechanically connected to the generator
24, the compressed air is supplied from the air supply port 26a,
and the expander 26 is operated by the supplied compressed air to
drive the generator 24. The generator 24 is electrically connected
to the power system 6 (indicated by a two-dot chain line), and the
power generated by the generator 24 is supplied to the power system
6. The air expanded by the expander 26 is exhausted from an exhaust
port 26b through the air passage 8d. For example, a screw type, a
scroll type, a turbo type, and a reciprocating type may be used as
the expander 26.
[0037] (Heat Medium Passage)
[0038] The first heat exchanger 18, a third heat exchanger 28a, a
high-temperature heat accumulating tank (heat accumulator) 30, the
second heat exchanger 22, and a low-temperature heat accumulating
tank 32 are sequentially provided in the heat medium passages 10a
to 10c. The heat medium circulates and flows among the first heat
exchanger 18, the third heat exchanger 28a, the high-temperature
heat accumulating tank 30, the second heat exchanger 22, and the
low-temperature heat accumulating tank 32. A type of the heat
medium is not particularly limited. For example, a mineral oil type
or a glycol type may be used as the heat medium.
[0039] In the first heat exchanger 18, the heat exchange is
performed between the compressed air in the air passage 8b
extending from the compressor 16 to the pressure accumulating tank
20 and the heat medium in the heat medium passage 10a extending
from the low-temperature heat accumulating tank 32 to the
high-temperature heat accumulating tank 30. Specifically, the
compressed air flowing in the air passage 8b becomes a high
temperature due to the compression heat generated during the
compression of the compressor 16, and the compressed air is cooled
by the heat exchange using the first heat exchanger 18. That is, in
the first heat exchanger 18, the temperature of the compressed air
falls and the temperature of the heat medium rises. The first heat
exchanger 18 is fluidly connected to the high-temperature heat
accumulating tank 30 through the heat medium passages 10a, 10b, and
the heat medium in which the temperature rises is supplied to and
stored in the high-temperature heat accumulating tank 30. A
three-way valve 34a is provided in the heat medium passages 10a,
10b, and one of the heat medium passages 10a, 10b through which the
heat medium flows can be selected by the three-way valve 34a.
[0040] A temperature sensor 36a that measures the temperature of
the heat medium is provided in the heat medium passage 10a
extending from the first heat exchanger 18 to the three-way valve
34a. The temperature of the heat medium measured by the temperature
sensor 36a is output to a controller 44 to be described later.
[0041] The third heat exchanger 28a is provided in the heat medium
passage 10b of the heat medium passages 10a, 10b. In the third heat
exchanger 28a, the heat exchange is performed between the heat
medium and the exhaust heat, the heat medium is heated, and the
exhaust heat is cooled.
[0042] The high temperature heat accumulating tank 30 heats and
stores the high-temperature heat medium supplied from the first
heat exchanger 18 or the third heat exchanger 28a. Consequently,
preferably the high-temperature heat accumulating tank 30 is
thermally insulated. The high-temperature heat accumulating tank 30
is fluidly connected to the second heat exchanger 22 through the
heat medium passage 10c, and the heat medium stored in the
high-temperature heat accumulating tank 30 is supplied to the
second heat exchanger 22 through the heat medium passage 10c.
[0043] In the second heat exchanger 22, the heat exchange is
performed between the compressed air in the air passage 8c
extending from the pressure accumulating tank 20 to the expander 26
and the heat medium in the heat medium passage 10c extending from
the high-temperature heat accumulating tank 30 to the
low-temperature heat accumulating tank 32. Specifically, the
temperature of the compressed air is raised before the expansion is
performed by the expander 26 using the high-temperature heat medium
in the high-temperature heat accumulating tank 30, thereby
improving power generation efficiency. That is, in the second heat
exchanger 22, the temperature of the compressed air rises and the
temperature of the heat medium falls. The compressed heat is
recovered to store in the high-temperature heat accumulating tank
30 the heat medium in which the temperature rises, and the
compressed air before expansion is heated by the second heat
exchanger 22 using the heat medium in which the temperature rises,
so that the power generation efficiency is improved. The second
heat exchanger 22 is fluidly connected to the low-temperature heat
accumulating tank 32 through the heat medium passage 10c, and the
heat medium in which the temperature falls is supplied to and
stored in the low-temperature heat accumulating tank 32 through the
heat medium passage 10c.
[0044] The low-temperature heat accumulating tank 32 stores the
low-temperature heat medium supplied from the second heat exchanger
22. The low-temperature heat accumulating tank 32 is fluidly
connected to the first heat exchanger 18 through the heat medium
passage 10a, and the heat medium stored in the low-temperature heat
accumulating tank 32 is supplied to the first heat exchanger 18
through the heat medium passage 10a.
[0045] In this manner, the heat medium circulates in the heat
medium passages 10a to 10c. The circulation of the heat medium is
performed by a pump 38 interposed in the heat medium passage 10a.
In the first embodiment, the pump 38 is provided on a downstream
side of the low-temperature heat accumulating tank 32, but a
position of the pump 38 is not particularly limited.
[0046] (Exhaust Heat Passage)
[0047] An exhaust heat source 40, the third heat exchanger 28a, and
a cooling tower 42 are sequentially provided in the exhaust heat
passages 12a to 12d.
[0048] The exhaust heat source 40 is a device that generates a
high-temperature gas (exhaust heat). For example, the exhaust heat
source 40 is an engine or a boiler. The exhaust heat source 40
communicates with outside air through the exhaust heat passages 12a
to 12d, and the high-temperature gas generated in the exhaust heat
source 40 is discharged to the outside air through the exhaust heat
passages 12a to 12d. In the first embodiment, the exhaust heat is
discharged from the exhaust heat source 40 in a form of the
high-temperature gas. However, the exhaust heat is not limited to
the gas but may be any fluid.
[0049] The exhaust heat passage 12a extending from the exhaust heat
source 40 is branched into two exhaust heat passages 12b, 12c
through a three-way valve 34b. The two branched exhaust heat
passages 12b, 12c merge into the exhaust heat passage 12d through
the three-way valve 34c. A cooling tower 42 that cools the gas in
the exhaust heat passage 12c is provided in the exhaust heat
passage 12c of the two exhaust heat passages 12b, 12c. The cooling
tower 42 of the first embodiment is a heat exchange type in which
the cooling water is used, but the cooling tower 42 is not
particularly limited thereto.
[0050] A temperature sensor 36b that measures the temperature of
the gas is provided in the exhaust heat passage 12a extending from
the exhaust heat source 40 to the third heat exchanger 28a. The
temperature of the gas measured by the temperature sensor 36b is
output to the controller 44 to be described later.
[0051] In the third heat exchanger 28a, the heat exchange is
performed between the heat medium in the heat medium passage 10b
extending from the first heat exchanger 18 to the high-temperature
heat accumulating tank 30 and the gas in the exhaust heat passage
12a. Specifically, the heat medium in the heat medium passage 10b
is heated using the high-temperature gas in the exhaust heat
passage 12a, the heat medium being supplied to the high-temperature
heat accumulating tank 30. That is, in the third heat exchanger
28a, the temperature of the gas falls and the temperature of the
heat medium rises.
[0052] A temperature sensor 36c that measure the temperature of the
gas is provided in the exhaust heat passage 12a extending from the
third heat exchanger 28a to the three-way valve 34b. A temperature
sensor 36d that measures the temperature of the gas is provided in
the exhaust heat passage 12c extending from the cooling tower 42 to
the three-way valve 34c. The temperatures of the gas measured by
the temperature sensors 36a to 36d are output to the controller 44
to be described later.
[0053] (Control Method)
[0054] The CAES power generation apparatus 2 includes the
controller 44. The controller 44 receives temperature values
measured by the temperature sensors 36a to 36d, and controls the
three-way valves 34a to 34c based on the temperature values.
[0055] In the case that a temperature Tg1 of the gas (exhaust heat)
measured by the temperature sensor 36b is higher than a temperature
Th1 of the heat medium measured by the temperature sensor 36a, the
controller 44 controls the three-way valve 34a, causes the heat
medium to flow in the heat medium passage 10b, and performs the
heat exchange using the third heat exchanger 28a. In the case that
the temperature Tg1 is lower than or equal to the temperature Th1,
the controller 44 controls the three-way valve 34a, does not cause
the heat medium to flow in the heat medium passage 10b, and does
not perform the heat exchange using the third heat exchanger 28a.
Thus, the temperature of the heat medium supplied to the
high-temperature heat accumulating tank 30 can be raised or
maintained.
[0056] In the case that a temperature Tg2 of the gas measured by
the temperature sensor 36c is higher than an exhaust heat reference
temperature Tth, the controller 44 controls the three-way valve
34b, causes the gas to flow in the exhaust heat passage 12c, and
cools the gas using the cooling tower 42. The exhaust heat
reference temperature Tth is determined by a law, and is an upper
limit value of the temperature of the exhaust heat that can be
discharged to the outside air. In the case that a temperature Tg3
of the gas measured by the temperature sensor 36d is still higher
than the exhaust heat reference temperature Tth after the cooling,
the controller 44 controls the three-way valves 34b, 34c, causes
the gas to repeatedly flow in the exhaust heat passages 12b, 12c,
and repeatedly cools the gas using the cooling tower 42 until
temperature Tg3 of the gas becomes lower than or equal to the
exhaust heat reference temperature Tth. In the case that the
temperature Tg3 of the gas becomes lower than or equal to the
exhaust heat reference temperature Tth by the cooling, the
controller 44 controls the three-way valve 34c to discharge the gas
to the outside air through the exhaust heat passage 12d. In the
case that the temperature Tg2 of the gas measured by the
temperature sensor 36c is already lower than or equal to the
exhaust heat reference temperature Tth, the controller 44 controls
the three-way valves 34b, 34c, causes the gas to flow in the
exhaust heat passages 12b, 12d, and discharges the gas to the
outside air without cooling the gas using the cooling tower 42.
[0057] As described above, in the first embodiment, the heat medium
heated by the first heat exchanger 18 can further be heated by the
third heat exchanger 28a, and the higher-temperature heat medium
can be stored in the high-temperature heat accumulating tank 30. As
described above, this configuration is effective in the case that
the exhaust heat from the exhaust heat source 40 outside the system
is higher than the heat medium heated by the first heat exchanger
18.
Second Embodiment
[0058] In a CAES power generation apparatus 2 according to a second
embodiment in FIG. 2, disposition of a third heat exchanger 28b is
changed. The second embodiment is substantially similar to the
first embodiment in FIG. 1 except for this point. Thus, the
description of the component similar to that in FIG. 1 will be
omitted.
[0059] In the second embodiment, the heat medium passage 10d is
branched from the heat medium passage 10c extending from the
high-temperature heat accumulating tank 30 to the second heat
exchanger 22. A three-way valve 34d is provided at a branch point,
and one of the heat medium passages 10c, 10d through which the heat
medium flows can be selected by the three-way valve 34d. The
branched heat medium passage 10d merges in the heat medium passage
10c on an upstream side of the second heat exchanger 22.
[0060] A temperature sensor 36e that measures the temperature of
the heat medium is provided in the heat medium passage 10c
extending from the high-temperature heat accumulating tank 30 to
the three-way valve 34d. The temperature of the heat medium
measured by the temperature sensor 36e is output to the controller
44.
[0061] The third heat exchanger 28b is interposed in the heat
medium passage 10d. In the third heat exchanger 28b, the heat
exchange is performed between the heat medium in the heat medium
passage 10d and the gas in the exhaust heat passage 12a.
Specifically, the heat medium in the heat medium passage 10d is
heated using the high-temperature gas in the exhaust heat passage
12a, the heat medium being supplied to the second heat exchanger
22. That is, in the third heat exchanger 28b, the temperature of
the gas falls and the temperature of the heat medium rises.
[0062] In the case that the temperature Tg1 of the gas (exhaust
heat) measured by the temperature sensor 36b is higher than a
temperature Th2 of the heat medium measured by the temperature
sensor 36e, the controller 44 controls the three-way valve 34d,
causes the heat medium to flow in the heat medium passage 10d, and
performs the heat exchange using the third heat exchanger 28b. In
the case that the temperature Tg1 of the gas is lower than or equal
to the temperature Th2 of the heat medium, the controller 44
controls the three-way valve 34d, does not cause the heat medium to
flow in the heat medium passage 10d, and does not perform the heat
exchange using the third heat exchanger 28b. Thus, the temperature
of the heat medium supplied to the second heat exchanger 22 can be
raised or maintained.
[0063] As described above, in the third heat exchanger 28b of the
second embodiment, the heat medium heated by the second heat
exchanger 22 can be preheated and a heating load of the heat medium
can be reduced in the second heat exchanger 22. As described above,
this configuration is effective in the case that the exhaust heat
from the exhaust heat source 40 outside the system is higher in
temperature than the heat medium supplied to the second heat
exchanger 22.
Third Embodiment
[0064] In a CAES power generation apparatus 2 according to a third
embodiment in FIG. 3, disposition of a third heat exchanger 28c is
changed. The second embodiment is substantially similar to the
first embodiment in FIG. 1 except for this point. Thus, the
description of the component similar to that in FIG. 1 will be
omitted.
[0065] In the third embodiment, a heat medium passage 10e is
branched from the heat medium passage 10a extending from the
low-temperature heat accumulating tank 32 to the first heat
exchanger 18. A three-way valve 34e is provided at the branch
point, and one of the heat medium passages 10a, 10e through which
the heat medium flows can be selected by the three-way valve 34e.
The branched heat medium passage 10e is fluidly connected to the
high-temperature heat accumulating tank 30.
[0066] The temperature sensor 36c that measures the temperature of
the heat medium is provided in the heat medium passage 10a
extending from the low-temperature heat accumulating tank 32 to the
three-way valve 34e. The temperature of the heat medium measured by
the temperature sensor 36e is output to the controller 44.
[0067] The third heat exchanger 28c is interposed in the heat
medium passage 10e. In the third heat exchanger 28c, the heat
exchange is performed between the heat medium in the heat medium
passage 10e and the gas in the exhaust heat passage 12a.
Specifically, the heat medium in the heat medium passage is heated
using the high-temperature gas in the exhaust heat passage 12a, the
heat medium being supplied to the high-temperature heat
accumulating tank 30. That is, in the third heat exchanger 28c, the
temperature of the gas falls and the temperature of the heat medium
rises.
[0068] In the case that the temperature Tg1 of the gas (exhaust
heat) measured by the temperature sensor 36b is higher than a
temperature Th3 of the heat medium measured by a temperature sensor
36f, the controller 44 controls the three-way valve 34e, causes the
heat medium to flow in the heat medium passage 10e, and performs
the heat exchange using the third heat exchanger 28c. In the case
that the temperature Tg1 of the gas is lower than or equal to the
temperature Th3 of the heat medium, the controller 44 controls the
three-way valve 34e, does not cause the heat medium to flow in the
heat medium passage 10e, and does not perform the heat exchange
using the third heat exchanger 28c. Thus, the temperature of the
heat medium supplied to the high-temperature heat accumulating tank
30 can be raised or maintained.
[0069] In the third heat exchanger 28c of the third embodiment, the
heat medium supplied to the high-temperature heat accumulating tank
30 can be heated in parallel with the heating of the heat medium by
the first heat exchanger 18, and the more heat medium can be stored
in the high-temperature heat accumulating tank 30. As described
above, this configuration is effective in the case that the exhaust
heat from the exhaust heat source 40 outside the system is higher
in temperature than the heat medium supplied to the first heat
exchanger 18.
Fourth Embodiment
[0070] In a CAES power generation apparatus 2 according to a fourth
embodiment in FIG. 4, disposition of a third heat exchanger 28d is
changed. The second embodiment is substantially similar to the
first embodiment in FIG. 1 except for this point. Thus, the
description of the component similar to that in FIG. 1 will be
omitted.
[0071] In the fourth embodiment, the air passage 8c extending from
the pressure accumulating tank 20 to the expander 26 is branched
into three air passages 8e to 8g. A three-way valve 34f is provided
at the branch point, and one of the air flow passages 8e to 8g
through which the compressed air flows can be selected by the
three-way valve 34f. The branched air passages 8e to 8g merge in an
air passage 8h through a three-way valve 34g. The merged air
passage 8h is fluidly connected to the air supply port 26a of the
expander 26.
[0072] A temperature sensor 36g that measures the temperature of
the heat medium is provided in the heat medium passage 10c
extending from the high-temperature heat accumulating tank 30 to
the second heat exchanger 22. The temperature of the heat medium
measured by the temperature sensor 36e is output to the controller
44.
[0073] Among the three air passages 8e to 8g, the second heat
exchanger 22 is interposed in the air passage 8g, and the third
heat exchanger 28d is provided in the air passage 8e. In the second
heat exchanger 22, the compressed air is heated by the heat medium
similarly to the first embodiment. In the third heat exchanger 28d,
the heat exchange is performed between the compressed air in the
air passage 8ec and the gas in the exhaust heat passage 12a.
Specifically, the compressed air in the air passage 8e is heated
using high-temperature gas in the exhaust heat passage 12a, the
compressed air being supplied to the expander 26. That is, in the
third heat exchanger 28d, the temperature of the gas falls and the
temperature of the compressed air rises.
[0074] In the case that the temperature Tg1 of the gas (exhaust
heat) measured by the temperature sensor 36b is higher than a
temperature Th4 of the heat medium measured by the temperature
sensor 36g, the controller 44 controls the three-way valves 34f,
34g, causes the compressed air to sequentially flow in the air
passages 8c, 8g, 8f, 8e, 8h, namely, heats the compressed air using
the second heat exchanger 22, and then further heats the compressed
air using the third heat exchanger 28d. In the case that the
temperature Tg1 of the gas is lower than or equal to a temperature
Th4 of the heat medium, the controller 44 controls the three-way
valves 34f, 34g, causes the compressed air to sequentially flow in
the air passages 8c, 8e, 8f, 8g, 8h, namely, heats the compressed
air using the third heat exchanger 28d, and then further heats the
compressed air using the second heat exchanger 22. Thus, the
temperature of the heat medium supplied to the expander 26 by both
the second heat exchanger 22 and the third heat exchanger 28d can
be raised or maintained.
[0075] In the third heat exchanger 28d of the fourth embodiment,
the compressed air before expansion can directly be heated using
the exhaust heat with no use of the heat medium or the like. As
described above, this configuration is effective in the case that
the exhaust heat from the exhaust heat source 40 outside the system
is higher in temperature than the compressed air supplied to the
expander 26.
Fifth Embodiment
[0076] In a CAES power generation apparatus 2 according to a fifth
embodiment in FIG. 5, disposition of a third heat exchanger 28e is
changed. The second embodiment is substantially similar to the
first embodiment in FIG. 1 except for this point. Thus, the
description of the component similar to that in FIG. 1 will be
omitted.
[0077] In the fifth embodiment, an air passage 8i is branched from
the air passage 8d extending from the exhaust port 26b of the
expander 26. A three-way valve 34h is provided at the branching
point, and one of the air passages 8d, 8i through which the air
flows can be selected by the three-way valve 34h. The branched air
passage 8i communicates with the outside air.
[0078] A temperature sensor 36h that measures the temperature of
the air is provided in the air passage 8d extending from the
expander 26 to the three-way valve 34h. The temperature of the air
measured by the temperature sensor 36h is output to the controller
44.
[0079] The third heat exchanger 28e is interposed in the air
passage 8i. In the third heat exchanger 28e, the heat exchange is
performed between the air in the air passage 8i and the gas in the
exhaust heat passage 12a. Specifically, the temperature of the air
exhausted from the expander 26 is lowered due to heat absorption
during the expansion, and the high-temperature gas in the exhaust
heat passage 12a is cooled by using the cold heat. That is, in the
third heat exchanger 28e, the temperature of the gas falls and the
temperature of the air rises.
[0080] In the case that the temperature Tg1 of the gas (exhaust
heat) measured by the temperature sensor 36b is higher than a
temperature Ta1 of the air measured by the temperature sensor 36h,
the controller 44 controls the three-way valve 34h, passes the air
in the air passage 8i, and performs the heat exchange using the
third heat exchanger 28e. In the case that the temperature Tg1 of
the gas is lower than or equal to the temperature Ta1 of the air,
the controller 44 controls the three-way valve 34h, does not cause
the air to flow in the air passage 8i, and does not perform the
heat exchange using the third heat exchanger 28e. Thus, the
temperature of the gas discharged from the exhaust heat source 40
can be lowered or maintained.
[0081] In the third heat exchanger 28e of the fifth embodiment, the
exhaust heat of the exhaust heat source 40 outside the system can
be cooled using the cold heat of the air exhausted from the
expander 26. As described above, the temperature of the air
exhausted from the expander 26 is lowered due to the heat
absorption during the expansion, and the energy efficiency of the
system can be improved by effectively utilizing the cold heat of
the exhaust air.
Sixth Embodiment
[0082] In a CAES power generation apparatus 2 according to a sixth
embodiment in FIG. 6, disposition of a third heat exchanger 28f is
changed. The second embodiment is substantially similar to the
first embodiment in FIG. 1 except for this point. Thus, the
description of the component similar to that in FIG. 1 will be
omitted.
[0083] In the sixth embodiment, a heat medium passage 10f is
branched from the heat medium passage 10c extending from the first
heat exchanger 18 to the low-temperature heat accumulating tank 32.
A three-way valve 34i is provided at the branch point, and one of
the heat medium passages 10c, 10f through which the heat medium
flows can be selected by the three-way valve 34i. The branched heat
medium passage 10f merges in the heat medium passage 10c on the
upstream side of the low-temperature heat accumulating tank 32.
[0084] A temperature sensor 36i that measures the temperature of
the heat medium is provided in the heat medium passage 10c
extending from the second heat exchanger 22 to the three-way valve
34i. The temperature of the heat medium measured by the temperature
sensor 36e is output to the controller 44.
[0085] The third heat exchanger 28f is interposed in the heat
medium passage 10f. In the third heat exchanger 28f, the heat
exchange is performed between the heat medium in the heat medium
passage 10f and the gas in the exhaust heat passage 12a.
Specifically, the high-temperature gas in the exhaust heat passage
12a is cooled using the heat medium in the heat medium passage 10f,
the heat medium being cooled by the second heat exchanger 22. That
is, in the third heat exchanger 28f, the temperature of the gas
falls and the temperature of the heat medium rises.
[0086] In the case that the temperature Tg1 of the gas (exhaust
heat) measured by the temperature sensor 36b is higher than a
temperature Th5 of the heat medium measured by the temperature
sensor 36b, the controller 44 controls the three-way valve 34i,
causes the heat medium to flow in the heat medium passage 10f, and
performs the heat exchange using the third heat exchanger 28f. In
the case that the temperature Tg1 of the gas is lower than or equal
to the temperature Th5 of the heat medium, the controller 44
controls the three-way valve 34i, does not cause the heat medium to
flow in the heat medium passage 10f, and does not perform the heat
exchange using the third heat exchanger 28f. Thus, the temperature
of the gas discharged from the exhaust heat source 40 can be
lowered or maintained.
[0087] As described above, in the third heat exchanger 28f of the
present embodiment, the exhaust heat from the exhaust heat source
40 outside the system can be cooled using the heat medium cooled by
the second heat exchanger. Additionally, the energy efficiency of
the system can be improved by effectively using the heat medium
cooled by the second heat exchanger.
[0088] Among the first to sixth embodiments, the first to fourth
embodiments are mainly aimed at recovering the exhaust heat from
the exhaust heat source 40 to improve the power generation
efficiency of the CAES power generation apparatus 2. The fifth and
sixth embodiments are mainly aimed at cooling the exhaust heat from
the exhaust heat source 40 to make the temperature of the exhaust
heat lower than or equal to the exhaust heat reference temperature.
These embodiments may be implemented by a combination thereof, and
FIG. 7 illustrates a configuration of a CAES power generation
apparatus 2 according to a seventh embodiment in which the first to
sixth embodiments are combined.
Seventh Embodiment
[0089] The CAES power generation apparatus 2 of the seventh
embodiment in FIG. 7 is the combination of the first to sixth
embodiments. Thus, a configuration of the CAES power generation
apparatus 2 of the seventh embodiment is substantially similar to
the configuration in FIGS. 1 to 6, so that the description will be
omitted. However, in the seventh embodiment, a pressure sensor 46
that measures the pressure in the pressure accumulating tank 20 is
provided in the pressure accumulating tank 20.
[0090] FIGS. 8A and 8B illustrate a control method of the seventh
embodiment. FIG. 8A illustrates the control method for recovering
and utilizing the exhaust heat from the exhaust heat source 40
outside the system as in the first to fourth embodiments. FIG. 8B
illustrates the control method for cooling the exhaust heat from
the exhaust heat source 40 outside the system as in the fifth and
sixth embodiments. These processes are performed in parallel.
[0091] As illustrated in FIG. 8A, when control of exhaust heat
recovery is started (step S8A-1), whether the compressed air is
being manufactured is determined (step S8A-2).
[0092] When the compressed air is not manufactured, whether the
temperature Tg1 of the gas (exhaust heat) measured by the
temperature sensor 36b is higher than the temperature Th3 of the
heat medium measured by the temperature sensor 36f is determined
(step S8A-3). When the temperature Tg1 of the gas is higher than
the temperature Th3 of the heat medium, a process of exhaust heat
recovery 3 is performed (step S8A-4). Otherwise, the heat medium
passage 10e is closed by switching the three-way valve 34e, and the
heat medium passage 10a toward the first heat exchanger 18 is
opened (step S8A-5). After these processes are performed, the
process proceeds to a process in step S8A-9 to be described later.
At this point, the process of the exhaust heat recovery 3 indicates
the exhaust heat recovery process in the third heat exchanger 28c
of the third embodiment.
[0093] In the case that the compressed air is manufactured, whether
the temperature Tg1 of the gas measured by the temperature sensor
36b is higher than the temperature Th1 of the heat medium measured
by the temperature sensor 36a is determined (step S8A-6). When the
temperature Tg1 of the gas is higher than the temperature Th1 of
the heat medium, the process of exhaust heat recovery 1 is
performed (step S8A-7). Otherwise, the heat medium passage 10b is
closed by switching the three-way valve 34a, and the heat medium
passage 10a toward the heat accumulating tank 30 is opened (step
S8A-8). After these processes are performed, the process proceeds
to a process in step S8A-9 to be described later. At this point,
the process of the exhaust heat recovery 1 indicates the exhaust
heat recovery process in the third heat exchanger 28a of the first
embodiment.
[0094] Subsequently, whether the temperature Tg1 of the gas
measured by the temperature sensor 36b is higher than the
temperature Th2 of the heat medium measured by the temperature
sensor 36e is determined, and whether the temperature Tg1 of the
gas is higher than the temperature Th4 of the heat medium measured
by the temperature sensor 36g is determined (step S8A-9). When the
temperature Tg1 of the gas is higher than the temperature Th2 of
the heat medium, the generator 24 generates the power (step S8A-11)
after the process of exhaust heat recovery 4 is performed (step
S8A-10). Otherwise, the power is generated (step S8A-11) after the
processes of the exhaust heat recoveries 2, 4 are performed (step
S8A-12). At this point, the processes of the exhaust heat
recoveries 2, 4 indicate the exhaust heat recovery processes in the
third heat exchangers 28b, 28d of the second and fourth
embodiments. However, as described in the fourth embodiment, the
process of the exhaust heat recovery 4 varies depending on whether
the temperature Tg1 of the gas is higher than the temperature Th4
of the heat medium, so that the process is performed based on the
value determined in step S8A-9. After these processes are
completed, the control of the exhaust heat recovery is ended (step
S8A-13).
[0095] As illustrated in FIG. 8B, when the control of exhaust heat
cooling is started (step S8B-1), whether a pressure P in the
pressure accumulating tank 20 measured by the pressure sensor 46 is
larger than a setting value Pth (step S8B-2). When the pressure P
is smaller than or equal to the setting value Pth, the process of
exhaust heat cooling 6 is performed (step S8B-3), and the process
proceeds to a process in step S8B-7 to be described later. When the
pressure P is larger than the setting value Pth, whether a power
demand is present is determined (step S8B-4). When the power demand
is present, the process of exhaust heat cooling 6 is performed
(step S8B-5). When the power demand is absent, the process of
exhaust heat cooling 5 is performed (step S8B-6). At this point,
the processes of the exhaust heat coolings 5, 6 indicate the
exhaust heat cooling processes in the third heat exchangers 28e,
28f of the fifth and sixth embodiments. After these processes are
completed, the process proceeds to a process in step S8B-7 to be
described later.
[0096] Subsequently, whether the temperature Tg2 of the gas
measured by the temperature sensor 36c is higher than the exhaust
heat reference temperature Tth is determined (step S8B-7). When the
temperature Tg2 of the gas is higher than the exhaust heat
reference temperature Tth, the three-way valve 34b is controlled
such that the gas flows in the exhaust heat passage 12c and the gas
is cooled by the cooling tower 42 (step S8B-8). Whether the
temperature Tg3 of the gas measured by the temperature sensor 36d
is higher than the exhaust heat reference temperature Tth is
determined after the cooling (step S8B-7). When the temperature Tg3
of the gas is still high, the three-way valves 34b, 34c are
controlled such that the gas repeatedly flows in the exhaust heat
passages 12b, 12c, and the gas is cooled by the cooling tower 42
until the temperature Tg3 of the gas becomes lower than or equal to
the exhaust heat reference temperature Tth (step S8B-8). When the
temperature Tg3 of the gas measured by the temperature sensor 36d
is lower than or equal to the exhaust heat reference temperature
Tth, the three-way valve 34c is controlled such that the gas is
discharged through the exhaust heat passage 12d (step S8B-9). When
the temperature Tg2 of the gas measured by the temperature sensor
36c is lower than or equal to the exhaust heat reference
temperature Tth, the gas is passed through the exhaust heat
passages 12b, 12c, and the gas is discharged without cooling the
gas using the cooling tower 42 (step S8B-9). After these processes
are completed, the control of the exhaust heat recovery is ended
(step S8B-10).
[0097] A temperature of a heat exchange target is always monitored
by performing the control in this way, and the exhaust heat from
the exhaust heat source 40 outside the system is prevented from
being heated or the heat medium or the compressed air is prevented
from being cooled. Further, sometimes unstable operation may be
performed because the renewable energy is used in the CAES power
generation apparatus 2. However, the cooling of the exhaust heat
and the heating of the heat medium or the compressed air can stably
be performed according to any operating condition by performing
various processes such as the processes of the exhaust heat
recoveries 1 to 4 and the processes of the exhaust heat coolings 5,
6.
Eighth Embodiment
[0098] In a CAES power generation apparatus 2 according to an
eighth embodiment shown in FIGS. 9A and 9B, both the compressor 16
and the expander 26 are replaced with two-stage types. The eighth
embodiment is substantially similar to the seventh embodiment in
FIG. 7 except for this point. Thus, the description of the
component similar to that in FIG. 7 will be omitted.
[0099] In the eighth embodiment, an exhaust heat recovery (cooling)
mechanism 48 including a third heat exchanger 28 in FIG. 9B is
provided at a position of a point X in FIG. 9A. Because the
compressor 16 and the expander 26 of the eighth embodiment are the
two-stage type, the exhaust heat recovery (cooling) is also
performed in an intermediate stage, and the larger number of the
exhaust heat recovery (cooling) mechanisms 48 is provided in the
eighth embodiment than that in the seventh embodiment.
[0100] The method for controlling the CAES power generation
apparatus 2 of the eighth embodiment is substantially similar to
that of the seventh embodiment.
[0101] As described above, the present invention can be applied
even if the compressor 16 or the expander 26 is a single-stage
type, a two-stage type, or a three-stage type or more.
[0102] In each of the embodiments described above, the target of
power generation by the renewable energy can be applied to all the
things, which are regularly (or repeatedly) replenished by natural
force such as wind power, sunlight, solar heat, wave force or tidal
power, running water or a tide, and geothermal heat and utilizes
irregularly fluctuating energy. The target of power generation by
the renewable energy can also be applied to the things in which the
power may be varied depending on a facility that consumes other
large power in a factory.
REFERENCE SIGNS LIST
[0103] 2: Compressed air energy storage power generation (CAES
power generation apparatus), 4: Power generation apparatus, 6:
Power system, 8a; 8b; 8c; 8d; 8e; 8f; 8g; 8h; 8i: Air passage, 10a;
10b; 10c; 10d, 10e; 10f: Heat medium passage, 12a; 12b; 12c; 12d:
Exhaust heat passage, 14: Motor (electric motor), 16: Compressor,
16a: Inlet air Inlet, 16b Discharge port, 18: First heat exchanger,
20: Pressure accumulating tank (pressure accumulator), 22: Second
heat exchanger, 24: Generator, 26: Expander, 26a: Air supply port,
26b: Exhaust port, 28; 28a; 28b; 28c; 28d; 28e; 28f: Third heat
exchanger, 30: High-temperature heat accumulating tank (heat
accumulator), 32: Low-temperature heat accumulating tank, 34; 34a;
34b; 34c; 34d; 34e; 34f; 34g; 34h: Three-way valve, 36; 36a; 36b;
36c; 36d; 36e; 36f; 36g; 36h; 36i: Temperature sensor, 38: Pump,
40: Exhaust Heat Source, 42: Cooling tower, 44: Controller, 46:
Pressure sensor, 48: Heat recovery (cooling) mechanism
* * * * *